However, when you bring up what Joseph Smith taught about that, in the April 1844 General Conference, they deny what he said about God the Father not always being God. That He was a human who worked His way up to Godhood, the way they can do. Mormons believe they can do that, but they have trouble with Smith teaching that’s what their God did.
I think many think Mormons just check their brains at the door, as if we just omit all logic and reason.
The King Follett discourse has not been canonized, but beyond that, let’s set why a Mormon would reject it.
Let’s look at Joseph’s own standard to prove his case:
So first: Joseph appeals to our own witness of the Holy Ghost -
“My first object is to find out the character of the only wise and true God, and what kind of a being He is; and if I am so fortunate as to be the man to comprehend God, and explain or convey the principles to your hearts, so that the Spirit seals them upon you, then let every man and woman henceforth sit in silence, put their hands on their mouths, and never lift their hands or voices, or say anything against the man of God or the servants of God again. But if I fail to do it, it becomes my duty to renounce all further pretensions to revelations and inspirations, or to be a prophet; and I should be like the rest of the world—a false teacher, be hailed as a friend, and no man would seek my life.”
Then he tells us how he supports his claim:
...for I am going to prove it to you by the Bible, and to tell you the designs of God in relation to the human race, and why He interferes with the affairs of man.
Here is the claim:
“I am going to tell you how God came to be God. We have imagined and supposed that God was God from all eternity. I will refute that idea, and take away the veil, so that you may see.”
As we can see, from the get go, this is unscriptural. (Moroni 8:18)
Later, he continues:
“What did Jesus say? (Mark it, Elder Rigdon!) The scriptures inform us that Jesus said, as the Father hath power in himself, even so hath the Son power—“
(Quoting John 5:26)
“to do what? Why, what the Father did. The answer is obvious—in a manner to lay down his body and take it up again. Jesus, what are you going to do? To lay down my life as my Father did, and take it up again.”
I personally do not see any scripture Joseph Smith could be getting this.
So there you have it. Joseph contradicted himself, I (personally) don’t feel the Spirit on it. And true to his word, that was basically his last address. He died two months later.
Thus, there is no standard by which any Mormon should be painted of believing the King Follett discourse just on the virtue of being a Mormon.